Here’s an interesting article on an economical car “survival” kit.

http://www.backwoodshome.com/articles2/yago104.html

Hmmm. Not a bad idea...but:

Calling it a ten day kit is a bit of a stretch

Relying on finding & treating water ?
I'd include a selection of water continers.

More tp.

Throwing a bunch of meds in an old prescription container? -- bad idea. Where's the immodium?

The food looks sufficent for perhaps 5-6 days. If you're looking for cheap cooks up with just water food, buy a 12 pack of ramen noodles. If you want cheap, survives the heat /cold in a car requires no cooking, get 2 boxes of granola bars.

I'd leave out the shampoo

Add a bunch of candles for heat, light and the psychlogical comfort.

More tools:

Leatherman, duct tape
orange help banner.
cell phone, pencil paper
mirror
Fire extinguisher